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Oil measuring.

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Old 07-12-2018, 03:48 PM
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Default Oil measuring.

I recently had a problem with oil and gas ratios mixing. I wanted a gas oil mixture of 30:1. I had a 7oz bottle of Lawn Boy 2 stroke oil and since there was no scale on the side of the bottle I used a small electronic food weight scale to measure out 4.26 oz. After obtaining the weight of 4.26 oz I added it to one US gallon of gas. I then used it to start my aircraft engine, a DLE 35. Someone told me this was the wrong way to measure out the proper amount of oil. He said measuring the oil in a calibrated measuring cup is different than weighing it. Was I wrong? It seemed to run the engine just fine.
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Old 07-12-2018, 04:46 PM
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j.duncker
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BAD NEWS Yes the ratio by weight is different to the ratio by volume.

GOOD NEWS Getting it exactly right is not critical. Anywhere between 25 to 1 and 40 to 1 will do just fine.
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Old 07-13-2018, 04:48 AM
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r ward
 
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think of it in "parts of one component" to "parts of the other component" then there is no confusion about weight or volume...... if one "part" is one ounce of gas or oil, then a 30:1 ratio will be 30 parts gas to one part oil. or 30 ounces gas to one ounce oil. this can applies whether you are measuring ounces, pounds, tons, quarts, gallons or swimming pools full. as long as you work the ratio in the same weight "parts" or the same volume for both "parts", the mix will be correct.

30 parts gas to 1 part oil
30 ounces gas to one ounce oil
30 gallons gas to one gallon oil
30 pounds gas to one pound oil
etc, etc,.....all the same ratio.
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Old 07-13-2018, 03:51 PM
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Default Cheap cups

Go to a speed shop buy a measuring cup or get a cooking measuring cup do the math and pour
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Old Yesterday, 06:16 AM
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No, switching from volume to weight will not give you the same actual ratio. Yes, the end goal is to have X number of molecules of oil for ever Y number for molecules of gas. The engine manufacturer worked out what that needed to be. Then they gave the end user a way to get there- volumetric measurements. They could have given us weight measurements, and you could figure out what the measurement by weight should be by measuring the density of both liquids and doing some 8th grade algebra. But there is no point in doing all of that. Use a measuring cup for your oil and fill your tank to exact gallon amounts, and you'll never have a problem.
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Old Yesterday, 09:50 AM
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Any cycle shop or jet ski etc shop will have it but this is what i use
https://www.amazon.com/Pit-Posse-PP3...o+cup+2+stroke
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